Re: [Evolution] trouble with Office 365 and OAuth2

[Milan Crha <mcrha redhat com>]

On Thu, 2020-01-09 at 10:39 -0500, Garrett Mitchener via evolution-list 
wrote:
> {"error":"invalid_client","error_description":"AADSTS7000218: The
> request body
>  must contain the following parameter: 'client_assertion' or
> 'client_secret'....

        Hi,
what you see in the "minibrowser" is an OAuth2 wizard provided by
Microsoft. The 'client_secret' is a parameter, which is sent to the
server. I looked into the source code and evolution-ews doesn't use
client_assertion, and it passes NULL (like 'none') client_secret. Maybe
the Microsoft page changed something and requires that client_secret,
though I know few users whom use OAuth2 with Office365 on a daily bases
and they would notice any problem very quickly. Thus, maybe, the way
the application is set up forces the use of the client_secret, which is
not needed otherwise.

That's only a guess though, I do not have any active account to confirm
this.

The latest (closed) bug about OAuth2 and Office365 is here:
https://gitlab.gnome.org/GNOME/evolution-ews/issues/58
Maybe you can find some information there.

Searching the web for the error code (AADSTS7000218) can shed some
light too. Few of the hits mention that the key was registered as for a
Web service, while evolution-ews requires Native application instead.

        Bye,
        Milan